How does DLS method defines the outcome of the rain affected cricket matches?

Significance of DLS method and how is it calculated
How does DLS method defines the outcome of the rain affected cricket matches?

Introduction

Cricket is a sport that has captivated fans around the world for centuries. With its rich history and complex rules, it's no wonder that cricket matches can be affected by various factors, such as weather conditions. Rain interruptions, in particular, can significantly impact the outcome of a match, leading to the need for a method to reset targets in order to ensure fair play. In these situations, the Duckworth-Lewis-Stern (DLS) method comes into play.

What is the DLS Method?

The DLS method is a mathematical formula used to calculate revised targets in rain-affected limited-overs cricket matches. It was introduced by statisticians Frank Duckworth and Tony Lewis in the late 1990s and has since become the standard method for resetting targets in interrupted matches. The DLS method takes into account the number of overs remaining and the number of wickets lost by the chasing team to determine a revised target for them to achieve victory.

The DLS method has been widely adopted by cricket governing bodies, including the International Cricket Council (ICC), and is used in various formats of the game, including One Day Internationals (ODIs), Twenty20 (T20) matches, and even prestigious tournaments like the Cricket World Cup and the Indian Premier League (IPL).

How Does the DLS Method Work?

The DLS method works by assigning a resource percentage to each team based on the number of overs they have remaining and the number of wickets they have lost. This resource percentage represents the team's ability to score runs based on their available resources. The higher the resource percentage, the more likely the team is to score runs at a faster rate.

To calculate the revised target using the DLS method, the resource percentages of both teams are compared. If the chasing team has fewer resources available, their target is revised downwards. On the other hand, if the chasing team has more resources available, their target is revised upwards to compensate for the advantage they have.

Understanding the DLS Table

The DLS method relies on a table of resource percentages that is used to calculate the revised target. This table provides the percentage of resources remaining based on the number of overs left and wickets lost. Here is an example extract from the table:

DLS reference table
Wickets Lost Overs Left Resource Percentage
0 2 100%
0 5 83.8%
0 10 32.5%
1 2 87.9%
1 5 77.6%
1 10 54.0%
2 2 68.2%
2 5 61.8%
2 10 40.0%

 

This table provides a quick reference for calculating the resource percentage based on the number of overs left and wickets lost. The resource percentage is then used to determine the revised target for the chasing team.

Examples of the DLS Method in Action

To better understand how the DLS method is applied in real cricket scenarios, let's explore a few examples:

Example 1: Premature Curtailment of Team 2's Innings

In a match between Team 1 and Team 2, Team 1 scores 250 runs in their allotted 50 overs. Team 2, batting second, manages to score 199 runs in 40 overs before rain interrupts play. As the rain refuses to relent, the match is abandoned, and a decision on the winner is required.

To calculate the revised target for Team 2, we need to consider the resource percentage available to them. At the start of their innings, they had 100% resource percentage. After 40 overs, with 10 overs remaining and 5 wickets lost, the resource percentage remaining is 27.5%.

As play is abandoned, all the remaining resource is lost for Team 2. Therefore, the resource percentage available for their innings is 100% - 27.5% = 72.5%. Since Team 2 has fewer resources available than Team 1, their target must be scaled down by the ratio of resources, which is 72.5/100.

Team 1 scored 250 runs, so Team 2's revised target is 250 x 72.5/100 = 181.25, or 181 runs. As Team 2 managed to score 199 runs, they have exceeded their revised target by 17.75 runs and are declared the winners by 18 runs.

Example 2: Interruption to Team 2's Innings

In another match, Team 1 scored 200 runs in their allotted 40 overs. Team 2, batting second, scores 140 runs in 30 overs before play is suspended due to rain. Five overs are lost during the suspension. We need to determine Team 2's revised target.

At the start of their innings, both teams had the same resource percentage available, which is 90.3%. After 30 overs, with 10 overs remaining and 5 wickets lost, the resource percentage remaining is 27.5%. When play is resumed, there are 5 overs left, and the resource percentage remaining is 16.4%.

The resource percentage lost during the suspension is 27.5% - 16.4% = 11.1%. Therefore, the resource percentage available for Team 2's innings is 90.3% - 11.1% = 79.2%. Since Team 2 has fewer resources available than Team 1, their target must be scaled down by the ratio of resources, which is 79.2/90.3.

Team 1 scored 200 runs, so Team 2's revised target is 200 x 79.2/90.3 = 175.42 or 176 runs. With 5 overs remaining and 5 wickets in hand, Team 2 requires a further 36 runs to achieve victory.

Example 3: Interruption to Team 1's Innings

In an ODI match, Team 1 scores 100 runs in 25 overs before their innings is terminated due to extended rain. Team 2's innings is also restricted to 25 overs. We need to determine the target score for Team 2.

Team 1 had 50 overs to bat, but rain led to the premature termination of their innings with 25 overs remaining and 2 wickets lost. From the resource percentage table, we can see that this interruption has deprived them of 61.8% of their resource percentage. Therefore, they had only 38.2% of resources available for their innings.

Team 2's innings is also 25 overs long, with no wickets lost. The resource percentage available for them is 68.7%. Team 2 has 68.7% - 38.2% = 30.5% more resources than Team 1. To calculate the revised target for Team 2, we take 30.5% of 225 (the average 50-over score in ODIs) and add it to Team 1's actual score of 100 runs.

Team 2's revised target is 100 + (30.5% of 225) = 168.63, or 169 runs. With 25 overs to achieve this target and 10 wickets in hand, Team 2 has a challenging task ahead.

Conclusion

The Duckworth-Lewis-Stern (DLS) method is a crucial tool in ensuring fair play in rain-affected limited-overs cricket matches. By taking into account the number of overs remaining and the number of wickets lost, the DLS method calculates revised targets that reflect the teams' available resources. This method has become widely accepted and is used in various formats of the game, including ODIs, T20 matches, and prestigious tournaments like the Cricket World Cup and the IPL. Understanding the DLS method allows fans and players to appreciate the complexities of the game and the impact weather conditions can have on match outcomes. So the next time rain interrupts a cricket match, you'll have a better understanding of how the DLS method comes into play and how revised targets are determined.

 


Posted 6 months ago